1. Field of the Invention
The invention relates to a device for filling the depressions in a cylinder of a printing machine (e.g., a screen roller) with a fluid. The invention also relates to a doctor blade device especially suited for this purpose, as well as to a process for changing the doctor blade device.
2. Discussion of the Prior Art
It is becoming increasingly important for printing machines to have, along with flexibility in web guidance, the capacity to change ink colors rapidly between printing jobs. Four-color printing machines, for example, must frequently be converted from a four-color printing mode with one web to a one-color printing mode with four webs. To minimize down time, such conversions must be carried out as quickly as possible. Conversion time is especially costly when printing machines are used for small runs e.g., when there are frequent changes in the type of production. Such printing machines include those connected to data networks for the decentralized printing of small runs. Printing machines of this type are described, for example, in German Patent Application DE 196 24 395.5. One time-consuming task in converting a printing machine is cleaning the inking unit.
German reference DE 39 11 839 A1 discloses what is known as a "rinse inking unit" for inking a screen roller. In this device, an inking channel is arranged below the screen roller. On both sides of the inking channel, doctor blades rest on the screen roller. Changing the ink in this device would require a time-consuming process of cleaning and exchange.